My avatar makes it obvious which one is my favorite. (For those who don't know what the avatar is) Arrogant Bastard. Stone Brewing in general changed my beer drinking.
For a starter list(many I have a hard time remembering)I would say(in no specific order):
Victory's Golden Monkey
Troeg's Trogenator
Sierra Nevada's Ruthless Rye
Stone Levitation
21st Amendment's Back in Black
Dogfish Head 60 min IPA
Dogfish Head Namaste
Oskar Blues's Old Chub
Yuengling
Bourbon County Stout

Then I also will drink run of the mill big name beers with friends of mine who aren't particular to my tastes in beer. I am in no way a beer snob and I love drinking beer with my friends...but when I buy my beer for home I will buy what I personally like.